Electronic devices such as laptop computers, cellular telephones, and other equipment are sometimes provided with optical components such as light sensors. Light sensors such as ambient light sensors may be used to make measurements on ambient lighting conditions. For example, an ambient light sensor may measure ambient light intensity so that display brightness adjustments may be made to a display in an electronic device.
To reduce ambient light sensor sensitivity to the presence of directional light sources such as lamps in the user's ambient environment, ambient light sensors may be provided with light diffusers. A light diffuser may diffuse incoming ambient light before the ambient light is measured by a photodetector associated with the ambient light sensor. Light diffuser structures may help reduce the sensitivity of an ambient light sensor to sources of directional lighting, but may scatter incoming light away from a photodetector in the ambient light sensor, thereby reducing ambient light sensor sensitivity.